JP2013522512A - Bent transducer, micro pump and micro valve manufacturing method, micro pump and micro valve - Google Patents

Abstract

A method of manufacturing a flexure transducer comprising a drive means and a membrane is provided, the method comprising providing a membrane (110) and drive means (210) (1010) and prestressing the drive means after joining. , Including applying (1020) a manufacturing signal (U _production ) to the driving means while joining the driving means to the membrane (110), wherein the manufacturing signal is of the same type as the operating signal for operating the bending transducer.
[Selection] Figure 1A

Description

  The present invention relates to a bending transducer, a micro pump and a method for manufacturing a micro valve, and a micro pump and a micro valve including the bending transducer manufactured by the method.

  According to the prior art invention, there are a number of different micro-membrane pumps and the driving concept used is electromagnetic, thermal and piezoelectric driving principles. However, almost all micro membrane pumps available on the market are driven by the piezoelectric drive principle.

  The compression ratio of the micro pump is an important parameter that determines the bubble tolerance and back pressure capability of the micro pump when the gas is the delivery medium. For fluid pumps, gas bubbles can enter the pump chamber at any time, and the back pressure capability for the fluid pump is actually also defined by the compression ratio (in addition to high operating diaphragm force and low valve leakage). The The compression ratio is the volume displaced by the pump membrane in a single blow or cycle, the so-called stroke volume, and the dead volume, ie the minimum volume remaining when the pump membrane pumps the medium contained in the pump chamber out of the pump chamber. Defined as the ratio between. The dead volume can be referred to as the volume difference between the maximum pump chamber volume and the stroke volume. The compression ratio of known micro pumps is relatively small and is in the range of 0.1-1.

  For example, Patent Application Publication No. EP0424087A1 has piezoelectric means that can be deformed in the first and second directions, i.e. up and down, by a voltage signal, thereby drawing liquid into the liquid reservoir of the micro pump, or liquid Disclosed is a micro pump that pumps out of a storage chamber. However, the micropumps described in EP0424087A1 are disadvantageous in that they contain a considerably large dead volume or have a small upward stroke and only a small stroke volume is obtained.

  In addition, the compression ratio of a micro-membrane pump driven piezoelectrically is usually defined by the following boundary conditions. When a positive voltage is applied to the piezoelectric membrane transducer, the membrane transducer can only deflect downward. Also, upward deflection is only possible by applying a negative voltage, and only about 20% of the downward stroke can be achieved so that the piezoelectric ceramic is not depolarized. Limiting membrane movement to downward movement makes it difficult to reduce dead volume and increase compression ratio. Thus, for example, looking at the micro-membrane pump of US 2005/0123420 A1 and the peristaltic micro-pump of US Pat. No. 6,261,066 B1 with respect to a conventional micro pump, the piezoelectric means moves in one direction. And / or the pump chamber is configured to adapt its contour to the membrane bending line to reduce dead volume and maximize compression ratio. This adaptation to the pump membrane bending line is labor intensive and costly with respect to production technology, and furthermore, the pump membrane does not deflect completely symmetrically due to, for example, distortion of the pump membrane in the bonding process, so the bending line Full adaptation to is usually not possible, thereby leaving gaps in the pump chamber that reduce the compression ratio. Furthermore, when the diaphragm ends are fixed, the stroke volume of the standard actuator is limited by boundary conditions. Finally, using silicon, this adjustment can only be accomplished in part by etching the wafer in several steps, thereby producing a high effect.

  US Patent Specification US 5,759,014 discloses a micro pump having a silicon pump membrane disposed on a glass base plate and inlet and outlet valves disposed opposite each other on both sides of the pump membrane. doing. The pump membrane has a shape that bulges upward in the rest position. The piezoelectric element is fixed to the surface of the film. When the piezoelectric element is driven, the film is displaced downward. The swollen shape of the membrane can be obtained by placing the chamber located above the sealed membrane under vacuum or by applying an oxide film with appropriate deformations on its upper surface under pre-stress. . The micropump according to US 5,759,014 is disadvantageous in that the dead volume caused by the connection space between the pump chamber and the inlet and outlet valves is still quite high, and the achievable bulge height of the membrane is Limited (and therefore only promoting a limited compression ratio) requires a significant amount of circular area of silicon oxide on the underside of the membrane to prevent membrane adhesion or adsorption. In addition, the lateral arrangement of the valves significantly increases the flow resistance of the pump chamber so that the stroke volume is only carried at a very low pump frequency that limits the maximum pump speed. Another disadvantage of buckling due to oxide coating or suction is the fact that when the piezoelectric is actuated by a positive voltage, the diaphragm cannot move to a completely flat position. Thus, the dead volume at the diaphragm boundary remains.

  US Patent Application Publication No. US 2009/015923 A1 describes prestressing of a pump diaphragm realized by laser welding of two metal layers. This application shows that prestressing of the diaphragm and pump chamber can be realized (apparently due to the thermal shock of the welding process). However, a large dead volume (which is even greater than the dead volume due to the oxide coating in US 5,759,014) also remains at the diaphragm boundary after actuation of the piezoelectric.

  In fact, as shown in FIG. 8, connecting the working membrane to the pump chamber by laser welding causes inevitable buckling of the membrane, which is not optimized with respect to minimized dead volume. FIG. 8 shows two schematic diagrams of a micro pump having a pump body 810 and a membrane 820 joined to the pump body by laser welding at the pump membrane boundary. The top view of FIG. 8 shows the pump membrane 820 in a pre-stressed non-actuated state, and the bottom view of FIG. 8 shows the same membrane 820 bent downward by a piezoelectric element 830 disposed on the pump membrane. As can be seen from the bottom of FIG. 8, the membrane 820 is not perfectly flat, and there is a pump membrane edge bulge or deflection 840 that causes increased dead volume due to the volume indicated by the membrane edge bulge 840. Indicated.

  US Patent Application Publication 2004 / 0036047A1 and US Patent Application Publication 2006 / 0027772A1 disclose normally closed valves. Formed by a stack of two silicon chips, the lower silicon chip includes the inlet and outlet of the valve, and the upper chip located above the lower chip is the recess of the valve chamber, the valve lip and the lower Includes a tappet on the side facing the tip, and a recess on the opposite side of the upper tip facing away from the lower tip to define the membrane, on the membrane above the tappet, to open the valve A piezoelectric drive is arranged to move the valve shutter formed on the chip downward. In the closed state, i.e. when the piezoelectric ceramic is not activated, the valve lip fluidically disconnects the valve inlet from the valve chamber. When the piezoelectric ceramic is operating, the piezoelectric ceramic moves the valve shutter connected to the membrane through the tappet downward. In this case, the valve lip no longer contacts the tappet and the valve is open. It has been observed that after the manufacture of the bulb, the membrane sometimes tends to bias downward. If these downward deflections are large, the valve may not meet the density requirements of a normally closed valve or may open with a slight reverse pressure on the membrane. This undesired flow of valve deactivation is disadvantageous and can even be critical in the field of medical technology or fuel cells.

Patent Application Publication EP0424087A1 US Patent Application Publication US2005 / 0123420A1 US Patent Specification US 6,261,066 B1 US Patent Specification US 5,759,014 US Patent Application Publication US2009 / 0158923A1 US Patent Application Publication 2004 / 0036047A1 US Patent Application Publication 2006 / 0027772A1

  The object of the present invention is to provide a method of manufacturing a bending transducer that can eliminate one or all of the above disadvantages of the prior art. A further object of the present invention is to provide a micro pump that can provide a high compression ratio and can be easily designed. Yet another object of the present invention is to provide a micro-valve having reliable density characteristics.

  The object of the present invention is to produce a bending transducer according to claim 1, a method for producing a micro pump according to claim 13, a method for producing a micro valve according to claim 14, and a micro according to claim 17. Achieved by a pump and a micro valve according to claim 20;

  Embodiments of the present invention provide a method of manufacturing a bending transducer comprising a drive means and a membrane, the method comprising the steps of providing the membrane and the drive means and pre-stressing the drive means after bonding. Applying to the drive means a manufacturing signal of the same type as the operating signal for operating the flexure transducer while joining the drive means to the membrane.

  Examples of bending transducers include a membrane and drive means coupled to the membrane, the drive means being joined to a bendable or deflectable membrane at the main surface of the drive means and applied to the drive means or The motion signal is converted into the motion of a bending transducer perpendicular to the main surface where the drive means is joined to the membrane. In other words, the drive signal is translated into a vertical motion (also called vertical range or direction) with respect to the main surface where the drive means is coupled to the membrane, parallel to the main surface where the drive means is joined to the membrane. A dimensional change (shrinkage or extraction) of the drive means (also called horizontal range or direction) is achieved. The degree of conversion is defined by the d31 coefficient of the driving means. Due to the manufacturing method, these bending transducers are prestressed or pre-swelled. This kind of prestressed flexure transducer can be used in micro pumps and micro valves to solve the above-mentioned problems.

  The drive means can be, for example, a piezoelectric drive means or any other drive means suitable for changing its volume or at least one dimension when a particular actuation signal or input is provided to the drive means. In the case of piezoelectric driving means, the manufacturing signal and the operation signal are voltages applied to the piezoelectric driving means. When a positive voltage is applied, the piezoelectric drive means contracts and moves the film in the direction of the film relative to the interface between the drive means and the film.

  Another embodiment of the drive means is, for example, a magnetically restrictive drive means or a drive means made of a magnetically restrictive material that changes its volume when a magnetic field is applied to the magnetically restrictive drive means. In this case, the manufacturing signal and the operation signal (signals given to the driving means during the subsequent normal operation) are electromagnetic fields.

  As will be apparent from the above embodiment, the manufacturing signal and the operation signal are the same type of signal (voltage for the magnetic field for the piezoelectric drive means, magnetically constrained drive means).

  The magnitude of the manufacturing signal (the voltage level of the manufacturing signal and the operating signal for the piezoelectric driving means, the strength of the magnetic field for the magnetically constraining driving means) can be the same for the manufacturing signal and the driving signal. Or it can be different.

  The polarity or direction of the manufacturing signal (the polarity of the voltage for the piezoelectric driving means, the direction of the magnetic field for the magnetically constraining driving means) can be the same for the manufacturing signal and the driving signal, or different For example, the direction can be reversed.

  If the polarity of the manufacturing signal and the operating signal are the same, the pre-given bulge of the bending transducer (of the membrane and / or drive means) achieved by the method of the invention is that of the membrane or bending transducer when the driving means is operated. The same as the corresponding stroke.

  In certain embodiments, depending on the application, the manufacturing signal has the same polarity as the manufacturing signal and the magnitude of the manufacturing signal has the same magnitude as the manufacturing signal, or has a smaller or larger magnitude. .

  Another embodiment of the present invention provides a method of manufacturing a micro pump, wherein the micro pump includes a membrane and a bending transducer and a driving means, the membrane forming the pump membrane and the first by the driving means. The pump body is connected to the pump membrane and a pump chamber is set between the pump body and the pump membrane, the method comprising: Manufacturing the bending transducer according to the method of the invention such that the pump membrane assumes a first pre-bulge shape at the first bulge position when the drive means is not activated.

  Yet another embodiment of the present invention provides a method of manufacturing a microvalve, wherein the microvalve includes a flexure transducer having a membrane and a drive means, the membrane forming the valve membrane to form the microvalve. The driving means is configured to move between a first position and a second position for opening and closing, the method comprising manufacturing a bending transducer according to the method of the invention.

  This embodiment provides a micro pump, which includes a flexure transducer that includes a membrane and a drive means, the membrane forming the pump membrane of the micro pump and the first bulge by the drive means. It is configured to move between the position and the second low bulge position, the pump body is connected to the pump membrane to set the pump chamber between the pump body and the pump membrane, and the driving means is activated When not, the pump membrane assumes a pre-bulge shape at the first bulge position and the flexure transducer is manufactured by the method of the invention.

  Further, the embodiment provides a micro-valve, which includes a bending transducer that includes a membrane and a drive means, the membrane forming a valve membrane and being activated by the drive means to open and close the micro-valve. Constructed to move between a first position and a second position, the bending transducer is manufactured by the inventive method.

  The embodiment of the present invention states that the micropump bulge 840 and corresponding dead volume shown in FIG. 8 is not the same as the corresponding stroke of the piezoelectric actuator in the prestressed diaphragm or membrane flexure shape. Based on discovering what happens by fact. In other words, prestressed film deflection due to prestressing during manufacturing (eg, oxide film or laser welding) is the film deflection caused by the piezoelectric actuating body during the micro pump drive. Different.

  Embodiments of the present invention can maximize the compression ratio by providing a pre-swollen method to the pump membrane, which is suitable for movement of the piezoelectric membrane or, in general, for movement of the working membrane. . In this way, the bulge 840 and the corresponding dead volume can be avoided or at least reduced. In order to achieve a pre-given bulge in the pump membrane that is suitable for the movement of the pump membrane caused by the drive means joined to the pump membrane, an embodiment of the method is that the pump membrane is pre-inflated when the drive means is not activated. Joining the drive means to the pump membrane so as to assume an elliptical shape. When the drive means is activated, the membrane is correspondingly positioned in the second less bulging position and the pump membrane tension or stress caused by the non-actuated drive means is reduced. In an embodiment of the method for producing a pre-swollen pump membrane, the drive means can be joined to the pump membrane, for example, when both have a planar shape. When joining the drive means to the pump membrane, the drive means and the pump membrane are in the first state when the drive means do not operate due to the application of different temperature coefficients and / or manufacturing signals to cause the drive means to contract laterally. At the swollen position, the upper swollen shape is taken. Actuation of the drive means causes the drive means to contract again (at the same time as reducing the tension of the pump membrane) and a downward deflection of the membrane indicates a deflection opposite to the pre-inflated state, driving or actuating the drive means If the drive signal for this is strong enough, the drive means is flat or minimally flat so that there is no bulge at the edge or can be ignored.

  In other words, the deformation of the membrane caused by the actuation of the drive means exhibits the opposite effect and deformation to the pre-given bulge, thus reducing at least the bulge or deflection 840 at the edge of the pump membrane.

  In other words, an embodiment of the present invention provides a micro pump, wherein the pre-expanded pump membrane bend shape is adapted to deformation caused by actuation of the drive means, whereby the pump membrane is second The pump membrane facing the pump body has a planar basic shape when it is in a position with little or no bulge and no back pressure is applied. The term “planar basic shape” is used as an anti-adhesion means in which the pump membrane has a planar shape when the pump chamber floor is a plane or a plane having a cavity, and the pump chamber floor or pump membrane is distributed on the pump chamber floor. When including protrusions, the pump membrane bulges slightly at the edge of the pump chamber floor, the outer anti-adhesive means are arranged from there towards the center of the pump chamber, and the planar shape provided by the anti-adhesion protrusion is It depends on rigidity.

  According to an embodiment of the method for manufacturing a micro pump, the drive means, for example the piezoelectric drive means, is in a contracted state, i.e. a state in which a predetermined production signal or voltage is applied to the drive means to cause the drive means to contract. And then the signal voltage is released. Upon release of the signal or voltage, the drive means is restored and moves upward away from the pump chamber to bend the membrane with the drive means.

  According to another embodiment of the method of manufacturing a micro pump, the pump membrane and the driving means, for example the piezoelectric driving means, are further heated to a predetermined manufacturing temperature and joined to each other at this manufacturing temperature, after which, for example, the normal external environment Cooled to temperature. Due to the different coefficients of thermal expansion of the drive means and the pump membrane, the bending transducer is prestressed in an additional way.

  This effect, on the other hand, can be used, for example, to produce a flexure transducer with increased prestress characteristics that can be used to provide a further increased pre-bulge height to the pump or valve membrane.

  On the other hand, if different temperature expansion coefficients of the driving means and the pump membrane lead to a pre-expanded shape usually downward (in the direction from the driving means to the pump membrane), the first achieved by opening the manufacturing signal A pre-given bulge on the pump membrane in the orientation of the pump membrane in the second orientation opposite the first orientation achieved by cooling the drive means and pump membrane to, for example, normal or ambient temperature. The manufacturing signal can be applied to be more than balanced with the pre-given bulge.

  This second aspect is advantageous for semiconductor films that typically have a lower coefficient of thermal expansion than piezoceramic or other piezoelectric drive means and that swell unnecessarily in advance downward. By applying a manufacturing signal for contracting the piezoelectric drive means to the piezoelectric drive means, the bulge given in advance downward can be more than balanced, and the bulge given in advance upward (from the pump membrane toward the piezoelectric drive means). Can be achieved.

  Thus, the normally closed valve described in US Patent Application Publication 2004 / 0036047A1 and US Patent Application Publication 2006 / 0027772A1 is non-stressed by prestressing the flexure transducer formed by the piezoelectric drive means and the silicon film. It can be closed or sealed more reliably in the operating state.

For a micro pump, the compression ratio c of the micro pump is defined by the ratio of the stroke volume ΔV and the dead volume V ₀ , ie c = ΔV / V ₀ . Thus, the two measurements can be considered initially primarily to increase the compression ratio. First, the stroke volume ΔV is increased, and secondly, the dead volume V ₀ is decreased. Embodiments of the present invention can handle both measurements and increase the compression ratio.

  The arrangement of input and output check valves below the membrane and in the pump body can achieve a high stroke volume and at the same time reduce dead volume. Furthermore, the pre-given bulge on the pump membrane only requires the use of or activation of the drive means and in particular the piezoelectric drive means in one direction (eg only downward), reducing the complexity of the drive means. The risk of depolarization is reduced in the case of piezoelectric drive means.

  Depending on the shape of the upper surface of the pump body forming the pump chamber floor and the shape of the pump membrane at the second low bulge position, the dead volume of the micro pump can be reduced. Thus, an embodiment of a micro pump does not include, for example, a spacer means or spacer structure disposed between the pump membrane and the pump chamber floor, but includes at least an essentially flat pump chamber floor, where the pump membrane is the second That is, when in an essentially flat position, the shape of the pump membrane and the shape of the pump chamber floor match, and the dead volume of the pump chamber is only basically defined by the dead volume of the valve well. Provide a valve.

  Embodiments of micro pumps can include a completely flat pump body, and all pump bodies (not just the part of the pump body defining the pump chamber floor) are essentially flat (e.g., It is a plane other than the valve pit). This is independent of whether silicon or other semiconductor materials, metals or polymer materials are used in the pump body and / or regardless of how the input and output check valves are manufactured and integrated. A completely flat surface of the seed or the pump body is easily manufactured. Thus, this type of embodiment can also reduce the complexity of production engineering.

  The dead volume of the inlet and outlet check valves and / or the valve wells of the inlet and outlet check valves-due to the placement of the inlet and outlet check valves opposite the pump membrane-reduce the sticking effect and pump from the pump chamber floor Allows easier movement of the membrane and corresponding upward movement of the pump membrane. In addition, micro-pump embodiments include an inlet and / or outlet check valve disposed opposite the central region of the pump membrane to reduce adhesion effects and / or reduce flow resistance.

  In a further embodiment, when the pump membrane moves to the second position and assumes a flat shape, for example, removes a valve well and / or depression in the valve side valve structure facing towards the pump chamber. Thus, the pump membrane is bonded directly to the upper surface of the pump membrane so that the pump membrane contacts the upper surface forming the pump chamber floor. In this context, “direct bonding” refers to a pump membrane using a bonding material, such as an adhesive, or without a bonding material (ie, no bonding material), for example, using ultrasonic welding, laser welding, or the like. Can be connected to the pump body, but without a spacing layer or component between the pump membrane and the pump body, the pump membrane is in the second flat position when the pump membrane is in the second flat position. It causes a gap between the membrane and the pump body.

  Thus, embodiments of the present invention provide a micro pump with self-contained operation, suitable for carrying a compressible medium such as gas, resistant to foam and independent of foam.

  When they are configured so that the micro pumps are still moving when the foam enters the pump chamber, the micro pumps are considered resistant to the foam and the foam (or part of the foam) is in the pump chamber Is carried by. However, the pump speed can vary while bubbles (or portions thereof) are present in the pump chamber.

  When the foam enters the pump chamber, the micro pump is not only moving, but if the pump speed is configured to be independent of the presence of foam in the pump chamber, the micro pump It is considered that they are independent.

The method of pre-bulging the membrane according to the present invention implements the height of the pre-bulge part with a particularly high range of pre-given bulges, e.g. with respect to the lateral expansion of the pump chamber, i.e. with respect to the diameter of the pump chamber. Not only a high pump chamber volume V _max , but especially a high stroke volume ΔV and finally a high compression ratio c.

In addition, method embodiments produce or produce pre-inflated pump membranes or valves, or generally pre-stress membranes, without the need for additional processing steps, such as the formation of additional oxide layers. Can do.
Examples will be described later with reference to the accompanying drawings.

FIG. 1A is a flow diagram illustrating an embodiment of a method of manufacturing a bending transducer. FIG. 1B shows an embodiment of a micro pump, where the pump membrane itself is in a first pre-inflated position or state (non-operating or resting). FIG. 1C shows the micropump embodiment of FIG. 1B in the second operating position or state, where the pump membrane takes a planar shape and abuts the pump chamber floor. FIG. 1D is a diagram showing an intermediate shape of the pump membrane when moving from a second less bulging shape, here a planar shape to a first bulging shape. FIG. 2A is a cross-sectional view showing an embodiment of a micro pump having piezoelectric drive means disposed on the top surface of the pump membrane (in a first non-operating or resting state). FIG. 2B is a cross-sectional schematic view showing the micro pump in FIG. 2A in a second operating state. FIG. 3A is a cross-sectional view illustrating a method for manufacturing a micro pump. FIG. 3B is a schematic cross-sectional view illustrating a method for manufacturing a micro pump. FIG. 4A is a schematic cross-sectional view illustrating an embodiment of a method for manufacturing a micro pump. FIG. 4B is a schematic cross-sectional view illustrating an embodiment of a method for manufacturing a micro pump. FIG. 4C is a cross-sectional schematic view illustrating an embodiment of a method for manufacturing a micro pump. FIG. 4D is a cross-sectional view illustrating an embodiment of a method for manufacturing a micro pump. FIG. 4E is a cross-sectional view illustrating an embodiment of a method for manufacturing a micro pump. FIG. 4F is an illustrative sectional view illustrating an embodiment of a method for manufacturing a micro pump. FIG. 5A is a cross-sectional schematic view showing the non-actuated state of a micro pump manufactured according to the method described on the basis of FIGS. FIG. 5B is a cross-sectional schematic view showing the operating state of a micro pump manufactured according to the method described on the basis of FIGS. FIG. 6 shows a standardized bend line (half pump membrane) from the center of the pump membrane to the edge of the pump membrane for different bulging effects or causes of bulging. FIG. 7A is a diagram showing a bending line of the pump membrane from the central portion of the pump membrane to the edge of the pump membrane for bonding the piezoelectric at 80 ° C. without applying a manufacturing voltage. FIG. 7B is a diagram showing a bending line of the pump membrane from the central portion of the pump membrane to the edge of the pump membrane for applying the manufacturing voltage of 73.6 V to couple the piezoelectric at 80 ° C. FIG. 7C is a diagram showing a bending line of the pump membrane from the center portion to the edge portion of the pump membrane for applying a manufacturing voltage of 73.6 V to couple the piezoelectric at 80 ° C. FIG. 7D is a diagram showing different bend lines of the pump membrane from the center to the edge of the pump membrane for applying a 178V manufacturing voltage to couple the piezoelectric at 80 ° C. FIG. 7E is an illustrative view showing a normally closed valve having a prestressed flexure transducer. FIG. 7F is an illustrative view showing a normally closed valve having a prestressed flexure transducer. FIG. 7FF is an illustration of a normally closed valve having a prestressed flexure transducer. FIG. 7G is an illustration showing a normally closed valve having a prestressed flexure transducer. FIG. 7H is a diagram illustrating a first embodiment of a normally open valve having a valve membrane that has been previously inflated. FIG. 7I is an illustrative view showing a second embodiment of a normally-open valve having a pre-inflated valve membrane. FIG. 8 is an illustrative view showing a conventional micro-pump with a pre-stressed membrane in an inactive and activated state.

  Same and / or equivalent elements are denoted by the same or equivalent reference numerals in the description of the figures below.

  FIG. 1A shows a flow diagram of an embodiment of a method of manufacturing a flexure transducer that includes a drive means and a membrane. In step 1010, the membrane and drive means are prepared. In step 1020, a signal of the same type as the operation signal for operating the flexure transducer is applied to the drive means while the drive means is joined to the membrane so that the drive means is prestressed after bonding. In other words, the manufacturing signal is the same type of signal that is applied to the drive means to bend or deflect the bending transducer and the membrane during normal driving of the bending transducer.

  The manufacturing signal is preferably opened after the coupling is finished or applied during the entire joining process.

  The joining itself can be performed by any suitable joining technique. The joining of the drive means to the membrane can be carried out without or with a joining material, for example by adhesion with an adhesive or by soldering with a liquid solder. Regardless of the specific bonding material, the bonding is performed by the bonding material arranged between the drive means and the membrane, and the manufacturing signal is only opened after the bonding material is cured, preferably fully cured. is there. If the voltage is fast, e.g. if it is released before the bonding material is fully cured, the driving means will change its size, thereby reducing the prestressed area after bonding of the driving means.

  As described above, in the case of transducer bonding in the change of the range in which the driving means is parallel to the surface of the driving means bonded to the membrane, the application of the manufacturing signal leads to a change in the size of the driving means. Changes can be either contraction or restoration. For example, the piezoelectric actuator contracts when a positive voltage is applied, and expands to some extent when a negative voltage is applied. Therefore, the embodiment sets the piezoelectric actuator in a contracted state and applies a positive manufacturing voltage to the piezoelectric actuator in order to keep the piezoelectric actuator in a contracted state until the end of bonding. After joining and after releasing the positive manufacturing voltage, the piezoelectric actuator attempts to restore or expand to its normal size or range when not operating, but the piezoelectric actuator It is joined so as to cover the entire principal surface for the film to be maintained in the lateral dimension, that is, the dimension parallel to the contact surface of the piezoelectric drive means having the film. Accordingly, prestress is applied to the piezoelectric drive means, the membrane, or generally the flexure transducer.

  If the piezoelectric actuator and membrane are not mechanically connected to any outer periphery or only connected to the outer periphery at the edge, for example in the case of micro pumps or micro valves, the production voltage is released. The result is that the piezoelectric actuator expands, but is not the normal size to expand when not bonded to the membrane. On the one hand, the membrane is also expanded due to the piezoelectric actuator. In this way, the piezoelectric actuator is pre-stressed compared to its normal dimensions, so that the piezoelectric actuator is pre-stressed, but is pre-stretched compared to its normal dimensions, The membrane is prestressed. At the same time, the driving means and the membrane are pre-swelled because prestress is applied in the direction toward the piezoelectric actuator.

  Piezoelectric actuators and membranes are not only fixed at their edges, but also see, for example, their centers (eg US patent application publication US 2004/0036047 A1, US patent application publication US 2006/0027772 A1 and normally closed valves according to FIGS. 7E-7G). ) If fixed, however, the membrane and piezoelectric actuator cannot bend in the direction toward the piezoelectric actuator, but prestress is applied and prestress is likely applied in the direction toward the piezoelectric actuator (the piezoelectric actuator is compressed) For example, prestress is applied in that it prevents unnecessary pre-swelling due to other manufacturing parameters).

  Similar considerations apply to any other drive means that can utilize bending transducers.

  In embodiments that use an adhesive to bond the drive means to the membrane, the adhesive often requires a certain predetermined manufacturing temperature above normal ambient temperature. In this way, different temperature coefficients of the drive means and the membrane can cause additional prestress on top of the prestress caused by the manufacturing signal. If the prestress due to the manufacturing signal and the prestress due to different temperature expansion coefficients are of the same type (for example, both lead to compression of the drive means after joining, or both lead to expansion provided to the drive means after joining) Prestress is added and prestress due to manufacturing signal and prestress due to different temperature expansion coefficients are different, for example, the reverse or reverse type (e.g. prestress by applying manufacturing signal causes compression and different temperature If the prestress by the factor causes a pre-given expansion and vice versa), the prestress can at least partially compensate for each other.

  Prestress due to different temperature expansion coefficients of the driving means and the membrane is used to achieve an increase in prestress and thereby achieve, for example, a higher pre-given bulge and stroke, or unnecessary directions due to different temperature coefficients Manufactured to a level and polarity such that unnecessary pre-given bulges are at least partially compensated, fully compensated, or over-compensated to achieve pre-given bulges and strokes in the required range and direction It is a further discovery of the present invention that it is used to set the signal.

  In an embodiment, the temperature coefficient of the membrane (eg, metal) is greater than the temperature coefficient of the drive means (eg, piezoelectric ceramic) and the manufacturing signal is such that the drive means is in a contracted state during bonding. In this case, the prestress due to both effects is of the same type (compression of the drive means), increasing the achievable prestress (pre-compressed compression) and mechanical of the membrane and / or drive means. As a result of this fixation, the achievable pre-expanded bulge height is increased.

  In a further embodiment, the temperature expansion coefficient of the membrane (eg, silicon) is less than the temperature expansion coefficient of the driving means (eg, piezoelectric driving means) and the manufacturing signal is such that the driving means is in a contracted state during bonding. Yes, the prestress due to different coefficient of thermal expansion is larger than compensated by the prestress due to the manufacturing signal.

  Another embodiment can use laser bonding or other bonding techniques to couple the drive means to the membrane, as described above, achieving pre-stress of the bending actuator and potentially pre-applying. Manufacturing signals can be applied during bonding to obtain the bulges that are produced.

  Since existing bonding processes and techniques can be used, method embodiments for manufacturing can be easily implemented. Only the means for applying the manufacturing signal to the drive means during the step of joining the drive means to the membrane must be predicted. This can be done more easily because the method in which the manufacturing signal is applied to the driving means can be similar to that in which the operating signal is applied. For a piezoelectric actuator, for example, during normal operation (later in the field), the same electrical connection used to apply the operating signal to the piezoelectric actuator applies the manufacturing signal during manufacturing or production Can be used to

  In the following, an embodiment of a micro pump including an embodiment of a bending transducer is described, the membrane of the bending transducer forming a pump membrane.

  1B and 1C show cross-sectional schematic illustrations of an embodiment of a micro pump that includes a pump membrane 110, a pump body 120, and a passive inlet check valve 130 and a passive outlet check valve 140. FIG. 1B shows a cross-sectional view of the first embodiment in a first swollen position. FIG. 1C shows a second less bulged micropump embodiment. In FIG. 1B, the drive means suitable for driving the pump membrane from the first bulge position to the second less bulge position is not activated. Accordingly, the drive means (also driver or actuator; not shown in FIG. 1B) is also referred to as inactive, inactive, inactive or dormant, and this position or state of the micro pump and pump membrane is also May be referred to as an inactive, inactive, inactive or resting position or state. In FIG. 1C, the drive means (not shown in FIG. 1C) is activated or activated to move the pump membrane 110 to the second position. Thus, with respect to the drive means, pump membrane and micro pump, this state or position can be referred to as an active or activated state or position.

  The pump membrane 110 has a first or upper surface 112 and a second or lower surface 114 disposed on the opposite side of the first surface 112. The pump body 120 includes a first or upper surface 122 and a second or lower surface 124 disposed on the opposite side of the first surface 122. The pump membrane 110 is connected to the pump body 120 at its periphery, and the pump chamber 102 is defined as the space or volume between the pump membrane 110 and the pump body 120. The pump body 120 has an inlet 126 and outlet 128 (pump inlet / pump outlet) and the upper side of the pump body, ie the side facing the pump membrane 110, in that the first valve 130 and the second valve 140 are arranged. Including cavities. The first valve 130 and the second valve 140 have a fluid connection, eg, a direct fluid connection, to the pump chamber 102.

  FIG. 1B shows an embodiment of the micro pump 100 where the inlet check valve 130 and the outlet check valve 140 are provided as a stack 170 of two semiconductor chips 150 and 160, and the semiconductor layer on the double valve structure 170 or The chip 150 is disposed on the lower semiconductor layer or chip 160, and the upper semiconductor layer 150 is mechanically constructed to provide a flap valve for the inlet check valve and a valve seat for the outlet check valve 140. The lower semiconductor layer 160 was constructed to provide a valve seat for the inlet check valve and a valve flap for the outlet check valve. The first and / or second semiconductor layers 150 and 160 may include silicon or other semiconductor material. Details regarding this type of layered valve structure are described, for example, in US Pat. No. 6,261,066B1. Other embodiments can include other inlet and outlet valves, such as active inlet or outlet valves, and can be composed of materials other than semiconductor materials, such as metals or polymers.

  As can be seen from FIGS. 1B and 1C, the first surface 122 of the pump body 120 is planar and faces the upper surface of the inlet and outlet check valves 130, 140, or in other words, the pump membrane 110. The upper surface 152 of the upper layer 150 is also planar and is at the same height level as the first surface 122 with respect to the vertical orientation of FIG. 1B. Under this common plane (defined by surfaces 152, 122), the inlet check valve 130 includes a cavity 132, eg, a cavity within the upper and lower layers 150, 160, and the outlet check valve 140, eg, the upper layer 150. , And are also referred to as “valve wells” 132 and 142.

  1B and 1C show a pump body 120 having a dual valve structure 170 inserted, other embodiments of micro pumps are valve structures 130 and 140 constructed directly within the pump. Or, in other words, valve structures 130 and 140 constructed directly in the material of the pump body 120.

  In other embodiments, the upper surface 152 of the valve structure 170 already forms the pump body 120 (see, eg, FIGS. 4A-4F and 5A-5B).

  In the following, the surface 122 of the pump body 120 and the upper surface 152 of the inlet and outlet check valves 130 and 140 are also referred to together as the first surface of the pump body or the pump chamber floor. Thus, the micropump 100 according to FIGS. 1B and 1C has a first surface that is essentially a planar first surface 122 or a basically planar pump chamber floor, ie, a plane other than the valve well cavities 132 and 142. Including the surface.

Within this context, the maximum capacity Vmax of the pump chamber 102 is the capacity between the pump body 120 and the pump membrane 110 and the valve wells 132 and 142 as shown in FIG. It should be mentioned that it includes volume. As can be further seen from FIG. 1C, in an embodiment where the pump membrane 110 is planar in the second less bulging position and abuts the first surface 122 of the pump body 120, the minimum volume or death The volume V ₀ is basically defined by the volume of the valve wells 132 and 142. The difference between these two volumes is also referred to as stroke volume ΔV, ie ΔV = Vmax−V ₀ . Since the compression ratio c is defined as c = ΔV / V ₀ , the micropump embodiment according to FIGS. 1B-1C provides a high compression ratio.

  As can be further seen from FIG. 1B, the reference H indicates the height of the pump chamber in the non-actuated state, ie the vertical distance between the pump body surface 122 and the pump membrane lower surface 114 at the pump membrane center 104. . The diameter D of the pump chamber or micropump is defined by the distance between the laterally opposed positions of the micropump, so that in the non-actuated pre-inflated state, the pump membrane 110 is generally a pump membrane. 110 contacts the pump body that matches the position where it is connected to the pump body 120 at its outer periphery.

  The pump chamber 102 is completely sealed from the surroundings (except for the inlet check valve 130 and the outlet check valve 140) by a connection between the pump membrane 110 and the pump body 120 at the outer periphery of the pump membrane 110. The outer periphery of the pump membrane 110 can have an angular shape, any point-symmetric geometry, or any other shape. Angular and point-symmetric perimeters provide improved pumping characteristics because they avoid distortion during operation.

  FIG. 1D shows a cross-sectional schematic view of the pump membrane 110 in the initial intermediate state 110 ′ when moving from the second planar state to the first pre-inflated state (see arrow A). When the drive means no longer operates, the pump membrane 110 begins to take on the pre-inflated state again. The upward movement of the pump membrane 110 begins, for example, by forming a small bulge in the central portion 104 of the pump membrane, as shown in FIG. 1D, which increases the height (see arrow A) and It spreads in the direction (see arrow B) and finally reaches a fully pre-swollen position as shown in FIG. 1B. A typical problem with a micro pump is that the pump membrane 110 tends to stick to the pump body 120 once it abuts the pump body 120. The arrangement of the inlet check valve 130 and the outlet check valve 140 existing below the pump membrane 110 reduces this adhesion effect due to the pump well formed by these valves. Further embodiments include an inlet valve 130 and an outlet check valve 140 disposed in a central region 126 extending from the central portion of the membrane and the corresponding central portion of the pump body 120. As can be seen from FIG. 1D, such a central arrangement of the inlet and outlet check valves, including the corresponding valve wells, makes it easier to create the initial bulge shape 110 ′ and further adhere as shown in FIG. 1D. Reduce the effect. The diameter of the central region 126 can range from less than 70% of the diameter D of the pump chamber 102, less than 50% or less than 30% of the diameter D.

  For example, for a micro-pump embodiment that moves the pump membrane 110 between a first pre-inflated position as shown in FIG. 1B and a planar second position as shown in FIG. The height H represents a stroke distance or a stroke height.

  Pump chamber volume Vmax and stroke volume ΔV can be increased by increasing pump chamber diameter D and / or stroke height H. As will be described below, an embodiment of a method of manufacturing a micro pump is the manufacture of a micro pump having a large diameter D, a high stroke height H, and a high ratio between the stroke height H and the pump chamber diameter D. Enable.

  In general, micro-pump or flexure transducer embodiments and micro-pump manufacturing methods are used, for example, when specific drive signals or manufacturing signals, also referred to as operating or activation signals, are applied thereto. One or more piezoelectric drive means, such as a monomorph piezoelectric element, multilayer piezoelectric element or piezoelectric stack element or any other drive means configured to contract laterally. These drive signals can be drive voltages, drive currents or any other physical means suitable for driving the drive means (eg for piezoelectric drive means). The same applies to manufacturing signals.

2A and 2B show cross-sectional schematic views of an embodiment of a micro pump 200 that includes a piezoelectric drive element 210 connected to the top surface 112 of the pump membrane 110. FIG. 2A is similar to FIG. 1B and shows a micro pump having the pump membrane 110 in a first pre-bulge position, and FIG. 2B is in a position where the second bulge is low, in this case a planar position. Indicates a micro pump. The piezoelectric drive element 210 includes an upper electrode on the first surface 212 (upper or upper surface) of the piezoelectric drive element 210 and a lower electrode on the second surface (lower or bottom surface) of the piezoelectric drive element 210. In addition, the second surface 214 is disposed on the opposing main surface (electrodes not shown) of the piezoelectric driving element 210. The upper electrode of the piezoelectric driving element 210 is electrically connected to the first contact 216, and the lower electrode of the piezoelectric driving element 210 is interposed, for example, through a conductive coating film disposed at least on a part of the surface 112 of the pump film. And electrically connected to the second contact 218 of the micro pump. The piezoelectric drive element 210 is bonded to the pump membrane 110 via, for example, an adhesive or other bonding technique. When a positive voltage is applied between the upper electrode 216 and the lower electrode 218, and between the first contact 216 and the second 218, respectively, the piezoelectric drive element contracts laterally and swells in advance The piezoelectric drive element is polarized so that the pump membrane 110 is lowered to the pump body 120 side. In FIG. 2A, no voltage (U = 0) is applied to the electrical contacts 216, 218. In other words, the piezoelectric drive element is not activated, and the pre-expanded pump membrane 110 indicates its pre-expanded position. In FIG. 2B, a positive voltage, for example U = U _MAX, is applied and the pump membrane 110 is bent down against the planar pump body 120 and is in contact therewith.

  The preferred embodiment of the micropump is that the pump membrane or drive membrane is in close contact with the essentially flat pump chamber floor or the pump chamber floor with a lower portion lower than the pre-inflated height H of the pump membrane in the upward direction. Based on the idea, the pump membrane is pre-inflated upward and a valve unit 170, eg, valve structure 130, 140, is formed in the pump chamber floor. The deformed or pre-deformed (ie, pre-inflated) membrane may be deformed or moved toward the pump chamber floor so that the pump membrane is in close contact with the pump chamber floor (see FIGS. 1C and 2B). it can. The dead volume Vo is thus basically only defined by the remaining dead volume of the valve wells 132, 142.

  As described on the basis of FIGS. 2A and 2B, the movement of the pump membrane 110 from the first pre-inflated position to the second planar position contracts laterally when a positive voltage is applied, and the voltage is Various methods that relax laterally when not applied and extend beyond the lateral length or dimensions of the relaxed state when a negative voltage is applied, for example, piezoceramic bonded onto a pump membrane 210 or other piezo drive such as a piezoelectric stack actuator can be achieved.

  In a further embodiment, the release of force onto the downwardly deforming pump membrane is applied via a piezoelectric stack actuator that is permanently coupled to the pump membrane.

  For example, a silicon microvalve valve well with respect to US Pat. No. 6,261,066B1 has a residual dead volume of, for example, about 360 nanoliters (0.36 microliters). A pump membrane having a pre-bulge shape similar to the bulge shape of a micro-pump pump membrane with respect to US Pat. No. 6,261,066B1, having a diameter D of 30 mm, produces a stroke volume of about 22 microliters. Can do. Therefore, the compression ratio c is 22 / 0.36 = 61. This compression ratio is several times higher than the compression ratio of known micro pumps in the range of 0.1 to 1.0. Through optimization, the compression ratio can be further increased since the silicon micro-pump valves described above can be further optimized with respect to their dead volume. Thus, for example, it is possible to produce a silicon valve having a remaining dead volume of about 50 nanoliters. By increasing the pump chamber, for example, the stroke volume can be increased to 50 microliters. Thus, a compression ratio of 50 microliters / 50 nanoliters = 1000 can be achieved. In combination with a piezo drive that is correspondingly strongly sized, a micro pump capable of producing a high negative pressure close to a vacuum or a very high positive pressure of several hundred bars. Can be obtained.

  In the following, an embodiment of the method of the micropump manufacturing embodiment of the invention will be described.

An embodiment of a method of manufacturing a micro pump associated with the method according to FIG. 1A will be described based on FIGS. 3A and 3B. According to an embodiment, the driving means, for example a piezoelectric driving means, are bonded on the pump membrane, and the pump membrane is pre-expanded due to the different temperature expansion coefficients of the piezoelectric driving means and the pump membrane. The pump membrane 110 is already bonded onto the pump body 120 including, for example, the inlet check valve 130 and the outlet check valve 140. The pump chamber floor can be flat, for example as shown in FIG. 3A, or at least essentially flat, as shown in FIG. 3A, and the pump membrane can be joined flat to the pump body. Can be done. In addition to the structure as described above including the pump body and the pump membrane, a driving means such as a piezoelectric driving means is provided, and a layer of adhesive 320 provided between the piezoelectric driving means 210 and the pump film 110 is provided. It is disposed on the pump membrane 110 having the same. The adhesive 320 can be placed, for example, on the lower surface of the piezoelectric drive means or on the upper surface of the pump membrane. The piezoelectric drive means is pressed onto the pump membrane with a predetermined manufacturing pressure using, for example, a silicon stamp to achieve a thin adhesive layer 320 with an even distribution of adhesive. The adhesive is cured at the manufacturing or joining temperature T _production .

Before the piezoelectric drive means 210 is placed on the pump membrane 110 or after the piezoelectric drive means (including the adhesive) is placed on the pump membrane 110, the pump body 120, the pump membrane 110 and The heating of the piezoelectric driving means 210 can be started, but the curing of the adhesive is carried out at the _production temperature T _production .

After curing of the pump adhesive, the device (including pump body, pump membrane and piezoelectric drive means) is cooled down. The piezoelectric driving element (i.e., a material consisting of either or contains piezoelectric drive element), for example, a temperature expansion coefficient of the piezoelectric ceramic of the temperature expansion coefficient alpha _piezo pump membrane (i.e., to or from the consisting material pump membrane contains) alpha is smaller than the _membrane, (when the piezoelectric drive means is not operated) shrinkage of the pump membrane is greater than the shrinkage of the bonded piezoelectric drive means on the pump membrane, therefore, the driving device comprising a pump membrane and the piezoelectric drive means Swells upward.

A micro pump according to an embodiment of a method for producing a micro pump is a pump or membrane material, for example a metal or metal alloy having a temperature expansion coefficient in the range of 10-25 × 10 ⁻⁶ / K at 20 ° C., for example 20 ° C. Materials and / or polymers having a temperature expansion coefficient in the range of 10 to 250 × 10 ⁻⁶ / K, and a piezoelectric ceramic having a temperature expansion coefficient in the range of 2 to 7 × 10 ⁻⁶ / K, for example at 20 ° C. A pump membrane having piezoelectric driving means such as can be included.

  The temperature expansion coefficient of the pump membrane can be 5 times or more or 10 times higher than the temperature expansion coefficient of the driving means. The higher the ratio between the temperature expansion coefficient of the pump membrane and the temperature expansion coefficient of the driving means, the greater the extent to which the pump membrane 110 swells in advance, thus increasing the height H, stroke height H, and stroke volume ΔV. Eventually, the compression ratio increases.

  Bonding of the piezoelectric ceramic 210 to the membrane 110 and curing of the adhesive at the manufacturing temperature may occur after the pump membrane is bonded to the pump body (as described above) or before the bonding of the membrane to the pump body is performed. Can be executed.

3A illustrates the bonding of the piezoelectric ceramic 210 to the top surface of the pump membrane 110, the application of the manufacturing pressure in FIG. 3A (see arrow 312) via the silicone stamp 310, and the curing of the adhesive 320 at the manufacturing temperature T _production . Show. FIG. 3B shows a pre-expanded membrane 110 in a pre-expanded shape due to a different temperature expansion coefficient after the pump has cooled down (adhesive not shown in FIG. 3B).

  An embodiment of a method for manufacturing the micro pump shown in FIG. 1A will be described with reference to FIGS. 4A-4F show cross-sectional schematics of the fabrication of a micro pump with a pre-expanded pump membrane, for example, the two-layer valve structure 170 forms the pump body 120 as shown in the context using FIG. 1B. The pump membrane is provided as a structured and thin third layer 410.

  As can be seen from FIG. 4A, the third layer 410 is thinned on its upper side or in the central region of the first surface 412 to provide a flexible pump membrane 110. Furthermore, as can be seen from FIG. 4A, the third layer 410 is a lower side arranged to face the first surface 412, for example in a further central part or region having a diameter greater than the diameter D of the central region. Or slightly thinner on the second surface 414. The pump membrane 110, the third layer 410, and the pump body 170 are each connected to each other so that the pump chamber 102 is defined between the pump body and the pump membrane.

  In a further embodiment, the third layer includes a flat second or lower surface 414 (ie, no cavities in the central region of the pump chamber, or in other words, the lower surface of the third layer). As a result, the pump membrane 110 is placed on the upper surface or pump chamber floor in the central portion of the pump body before the pre-bulge structure is implemented. Abut. The remaining dead volume of such an embodiment is only basically defined by the valve wells 132 and 142.

  The manufacture of such a laminated pump structure is described, for example, in US Pat. No. 6,261,066. The three layers 150, 160 and 410 are made of, for example, a semiconductor material, such as silicon or other material.

  In other words, FIG. 4A shows the micro pump before the pre-inflated structure and before bonding the piezoelectric ceramic to the membrane.

  In FIG. 4B, a piezoelectric ceramic 210 having a layer of adhesive 320 on its lower surface is disposed on the upper surface 412 of the film 110.

  FIG. 4C shows a micro pump structure having a piezoelectric ceramic 210 disposed in a layer of film 110 and adhesive 320 between the piezoelectric ceramic and the pump film.

  In FIG. 4D, for example, the piezoelectric ceramic 210 is pressed onto the pump membrane 110 at a predetermined manufacturing pressure using a silicone stamp 310. The manufacturing pressure is such that the adhesive 320 is preferably evenly distributed on the bonding surface of the piezoelectric ceramic and the pump membrane essentially uniformly and peaks between the conductive layer on the top surface of the membrane and the lower electrode of the piezoelectric ceramic. Contacts are made to provide an adhesive layer thickness that is small enough to electrically connect both. In order to obtain a peak contact, an insulating or non-conductive adhesive can be used to couple the piezoelectric drive means to the pump membrane, but still electrically connect the lower electrode of the piezoelectric drive means Yes. In the step represented by FIGS. 4C and 4D, it should be shown that the adhesive has not yet been cured.

In FIG. 4E, a manufacturing voltage U _production is applied to the piezoelectric drive means 210 (eg, a piezoelectric ceramic or a piezoelectric stack actuator) so that the piezoelectric drive means contracts. After contraction of the piezoelectric drive means, the adhesive is cured while applying the manufacturing voltage U _production and further maintaining the manufacturing pressure via the silicon stamp 310.

  After the adhesive is cured, the production voltage and pressure are released.

In other words, the piezoceramic is glued onto the pump membrane and a positive production voltage U _production is applied to the piezoelectric drive element during the curing of the adhesive. Therefore, the piezoelectric drive means ceramic shrinks and adheres to the membrane in a contracted state. The production voltage is only released after the adhesive is cured.

  After the voltage is released, the piezoceramic is relaxed or stretched again to pre-inflate the drive (ie pump membrane and piezoceramic) as shown in FIG. 4F (adhesive not shown in FIG. 4F). The

  Thus, the pump structure of FIG. 4A was modified to include a prestressed or pre-inflated membrane or diaphragm. Depending on the pump chamber volume and dead volume, as described, such an embodiment can achieve a high compression ratio.

  Although an embodiment of a micro-pump manufacturing method has been described with respect to the membrane 410 already adhered to the pump body 170, in another embodiment, before the pump membrane or third layer is bonded to the pump body, A given bulge (ie positioning of the piezoelectric ceramic and curing of the adhesive under the production voltage) can also be performed.

FIG. 5A shows a cross-sectional schematic view of a micro pump made by the method according to FIGS. FIG. 5A shows a micro pump having a membrane 110 pre-inflated in a non-actuated state (U = 0V). FIG. 5B shows the micropump of FIG. 5A in an activated state, where the pump membrane 110 has a basically flat shape. The pump membrane 110 is moved to the second planar position by applying an operating voltage U equal to the _production voltage U _production , for example 300V, when no back pressure or back pressure is applied. When back pressure is applied, the output check valve 140 opens and is sufficient in the pump chamber to overcome the necessary threshold pressure differential that allows fluid in the pump chamber to be pumped out of the micro pump. In order to create pressure, the drive or operating voltage U can be increased to a voltage value higher than the production voltage U _production .

  As previously mentioned, the method described on the basis of FIGS. 4A-4F can be combined with the method described on the basis of FIGS. 3A and 3B, providing a further method of manufacturing a micro pump, A pre-given bulge can also be achieved.

  In the embodiments described above, the pump membrane is pre-stretched by the drive means for different coefficients of thermal expansion and / or for restoring the piezoelectric drive means after the production voltage has been released. Thus, when the drive means is actuated to bend the pump membrane down, for example when the pump membrane is in the second planar position, the stress on the pump membrane due to elongation is partially or fully released. .

  For example, embodiments of micropumps using piezoelectric drive means, such as piezoceramics, ie piezoelectric laminates, have a large stroke force and stroke length, or a relatively low voltage, compared to electrostatic or electromagnetic drive means. Provide height.

  To reduce or avoid the sticking effect of the pump membrane on the pump body when the pump membrane abuts the pump body, for example, in a star shape extending radially from the inflow check valve or the respective valve well Placed depressions can be placed, or small hubs or protrusions that extend from the pump chamber floor or pump membrane to the pump chamber can be implemented.

  Although primarily micro-pump embodiments have been described that include inflow check valves and outflow check valves 130 and 140 made of semiconductor material, such as silicon, other embodiments of micro-pumps can be made of different materials such as Similar or different passive inflow and outflow check valves made of metal or polymer independent of the pump body in which they are incorporated may be included.

  Furthermore, although an embodiment of a micro-pump is shown that includes an inflow check valve and an outflow check valve 130 and 140 integrated or arranged in the pump body, other embodiments include, for example, a pump membrane and a pump body. A valve disposed laterally may be included.

  Further embodiments of the micro pump can include a pump body in which inflow and outflow check valves are integrally formed, as described, for example, with reference to FIGS.

  Other examples include pump bodies having integrally formed valve inlet and valve outlet structures 130 and 140 having materials such as steel, stainless steel or spring stainless steel, synthetic materials or polymers, etc. The pump body includes one or more layers to form a valve structure. Thus, further examples of micro pumps include pump bodies and pump membranes made of metal, synthetic materials, polymers or laminates thereof. Compared to silicon pump bodies and pump membranes, pump bodies and pump membranes made of metal or polymer are less costly in manufacturing and offer more flexibility, for example, provide a lower Young's modulus .

  Another embodiment of the present invention provides a drive membrane for the micropump, which moves between a pre-bulged or pre-deformed position and an essentially flat position, The non-uniform portion of the surface arranged to face towards the pump membrane is smaller than the membrane stroke height H.

  Such a micro pump includes a driving membrane that is pre-expanded upward. Such an embodiment can include a piezoceramic bonded onto the drive membrane.

  Such an embodiment of a micro pump can include a membrane that is moved between two positions by a piezoelectric laminated actuator, the membrane being permanently bonded to the piezoelectric laminated actuator.

  In the following, the results of some simulations of the pump membrane shape will be discussed to explain further aspects and / or effects of embodiments of the present invention.

  The bending shape of the pump membrane was calculated for silicon piezoelectric pumps (micro pumps with or consisting of silicon and piezoelectric drive means as drive means) using finite element analysis. Due to the shape of the micro pump, the parameters of the secondary silicon pump membrane with a side length of 6.3 mm and the thickness or height of the pump membrane itself, the piezoelectric drive means with a thickness or height of 150 mm are used. The ratio of the side length of the piezoelectric driving means is 0.8 with respect to the side length of the pump film. The bent shape is shown from its center to the edge of the pump membrane parallel to an axis through the center of the membrane.

  The bending shape of the pump membrane was calculated for silicon piezoelectric pumps (micro pumps with or consisting of silicon and piezoelectric drive means as drive means) using finite element analysis. Due to the shape of the micro pump, the parameters of the secondary silicon pump membrane with a side length of 6.3 mm and the thickness or height of the pump membrane itself, the piezoelectric drive means with a thickness or height of 150 mm are used. The ratio of the side length of the piezoelectric driving means is 0.8 with respect to the side length of the pump film. The bent shape is shown from its center to the pump membrane boundary parallel to an axis through the center of the membrane.

  Different characteristic bent shapes are: (1a) only the thermodynamic tension caused by the different temperature expansion coefficients of the materials used, (1b) only the bending actuator effect by applying an electric field to the piezoelectric drive means, (2) only the effect of application of pressure (different pressure between the upper and lower sides of the pump membrane), (3) only the bending actuator effect due to the structural oxide film with inherent tension (structure: of the piezoelectric drive means at the same position) Instead, it is determined for the case due to the case of oxide film).

  Cases (1a) and (1b) are identical in terms of the effects and characteristics of bending their shape and are summarized as case “U / T”. Case (2) is called “P” and case (3) is called “Ox”. In FIG. 6, these three above-mentioned “pure cases” bend shapes are normalized, that is, a height z that expands the maximum bend value zo for the corresponding case and a width that expands the length xo of the silicon film. It is indicated by a directional position x. In the lower part of the diagram of FIG. 6, a pump membrane 120 having a length xo (from the center to the edge) is shown, the length of the piezoelectric drive means from the center to the portion of the pump membrane length of 0.8. Is shown (side length ratio 0.8). In FIG. 6, reference numeral 610 indicates the case U / T, reference numeral 620 indicates the case P, and reference numeral 630 indicates the case Ox. FIG. 6 shows the normalized bend shape for half of the pump membrane (from center to edge) for different bend effects or cases.

  In a first order approximation, all these effects of temperature, pressure and oxide tension on bend (bend shape) and drainage volume can be expanded linearly and can be linearly superimposed.

In the following, the bending of the pump membrane and the drainage volume or stroke volume are described with respect to their absolute values. The parameters for the simulation are the side area or surface 6300 × 6300 mm ² , thickness 50 mm, Young's modulus 166 GPa (Poisson value 0.3) with respect to the silicon film. The lateral width and length are 0.8 times the lateral width and length of the silicon film, the thickness is 150 mm, and the Young's modulus is 90 GPa (Poisson value 0.3). Temperature expansion coefficient α, relative to silicon is 0.3 × 10 ^-6 / K, in the piezoelectric drive, the difference between ^{5 × 10 -6 /K(2.7×10 -6 / K} ) is there. The d31 coefficient of the piezoelectric drive is 330 × 10 ⁻¹² m / V.

FIG. 7A shows a transverse dimension in which the bent shape from the center (left side of the diagram) to the edge (right side of the diagram) of the pump membrane in the prior art is normalized to the half length or width x ₀ of the pump membrane. Shown in diagram with longitudinal dimension z shown as absolute value in x and micrometers. FIG. 7A shows that when the piezoelectric drive means is mounted or assembled at 80 ° C. without applying a production voltage (U _production = 0), there is no pressure (P = 0), and −50V (reference number 712). ), 0V (reference numeral 714) and 150V (quotation numeral 716), the bent shape at 20 ° C. is shown. In the figure, the abbreviation “w” was used for “with” and the abbreviation “wo” was used for “without”.

As can be seen from FIG. 7A, if the bonding of the piezoelectric drive means to the pump membrane is performed by curing the adhesive at 80 ° C., the measurement at room temperature (20 ° C.) already results in a temperature difference of −60 ° C. The membrane bends 5 μm downward. In other words, due to the fact that the temperature expansion coefficient of the silicon pump membrane is smaller than the temperature expansion coefficient of the piezoelectric drive means, when the pump film and the piezoelectric drive means are cooled down to, for example, room temperature, the increased production temperature T _production The bending of the piezoelectric drive means to the pump film causes the pump film to swell in advance downward (negative z value). The bulge previously imparted to the pump membrane down, for example, cannot use a flat pump chamber floor and needs to increase the dead volume and / or adapt the pump chamber floor to the bend line of the pump membrane, It is disadvantageous because it is complicated and expensive. Furthermore, since the silicon film has a smaller coefficient of thermal expansion than the piezoelectric drive means and the adhesive used to bond the piezoelectric drive means to the pump film is cured at a temperature higher than normal ambient or operating temperature, In the case of a silicon film, the predetermined bulge given in advance is almost unavoidable.

  As described above, when the temperature expansion coefficient of the pump film is higher than the temperature expansion coefficient of the piezoelectric driving means, the pump film is previously swollen on the opposite side, that is, upward after the pump film and the piezoelectric driving means are cooled to, for example, room temperature. Given. In this way, a pump membrane that is positive or pre-bulged upwards can be easily made without the need for additional processing steps, such as the formation of an additional oxide layer.

  The bent shape 714 can be considered as the bent shape that the pump membrane takes when the drive means is not activated and no other external pressure or influence is applied to the pump membrane. As can be seen from FIG. 7A, the height z (or H) is about −5.35 μm in the center of the pump membrane. When a negative driving voltage of −50V is applied (see reference numeral 712), the piezoelectric driving means expands, so that the pump membrane is deformed upward, and when a positive voltage of + 150V is applied as the driving voltage, The pump membrane bends further downward due to the contraction of the piezoelectric driving means (see reference numeral 716).

By applying a voltage, for example the production voltage U _production, to the piezoelectric drive means while joining the piezoelectric drive means to the pump membrane, the effect shown in FIG. 7A (downward bending of the pump membrane) is corrected and the production provided during joining. Partially compensated according to the voltage, fully compensated or overcompensated. For example, in order to compensate for a temperature difference of 60 ° C., such as when bonding of the piezoelectric drive means to the pump membrane is performed at 80 ° C. and the micropump is later operated or used at 20 ° C. In order to compensate for the negative pre-given bending caused by the temperature difference, i.e. to obtain a planar shape when the drive means is not operating, a manufacturing voltage of 73.6 V is required. Because the bend shape is the same (ie, normalized same), when no external pressure and voltage are applied, the stroke and volume are compensated simultaneously and the pump membrane assumes a flat shape.

  FIG. 7B shows a diagram of a half-bend shape from the center to the edge of the pump membrane for piezoelectric bonding at 80 ° C. and a manufacturing voltage of 73.6 V (similar description to FIG. 7A). Reference numeral 722 indicates a bent shape of the pump membrane when the drive voltage is −50 V and there is no external pressure P at 20 ° C. Reference numeral 724 indicates a bent shape of the pump membrane at 20 ° C. and 0 V (no driving voltage) and no external pressure. Reference numeral 726 indicates a driving voltage of 20 V at a driving voltage of 150 V and an external pressure of 1 bar. 2 shows the bent shape of the pump membrane. As can be seen from FIG. 7B, the piezoelectric drive means is bonded at 80 ° C., and during the bonding, a manufacturing voltage of 73.6 V is applied, so that it is negative or pre-applied downward caused by a temperature difference of −60 ° C. Bendings and positive or pre-bending bendings by opening the production voltage compensate each other, so that the pump membrane takes a simple shape (see reference numeral 724) when the piezoelectric drive means is not activated. . As already explained with reference to FIG. 7A, application of a negative voltage to the piezoelectric drive means biases the pump membrane upward (see reference 722), while application of a positive voltage causes the pump membrane to Inflate downward (see reference numeral 726).

  FIG. 7C shows a diagram similar to one of FIG. 7B (for the same pump membrane as in FIG. 7B). The two upper bent shapes are the same. However, the reference number 728 refers to the bent shape resulting from applying a driving voltage of 150V and an external pressure of 1 bar. As can be seen, applying a driving voltage of 150V causes the pump membrane to deform downwards even though 1 bar of counter pressure P is applied to the pump membrane.

  Below, the piezoelectric drive means is bonded to the pump membrane (at 80 ° C.) so that the pump membrane just contacts or abuts the top surface of the pump body when a drive voltage of 150 V is applied at a specific counter pressure. In the meantime, which voltage is to be applied is calculated as a sample. The pressure is derived from the resulting compression ratio.

  FIG. 7D shows a diagram of the bent shape of the pump membrane, with a representation similar to that in FIGS. 7A-7C, where the piezoelectric drive means bonding was performed at 80 ° C. with a production voltage of 178V. For the pump membrane. Reference numeral 732 indicates a bent shape of the pump membrane from the center portion to the edge portion when there is no pressure at 20 ° C. and −50V. Reference numeral 734 indicates a bent shape of the pump membrane in a non-operating state (driving voltage U = 0 V) and no external pressure (P = 0). Reference numeral 736 is given in advance by gluing the piezoelectric drive means at the same pump membrane (80 ° C. and 178 V when a production voltage of 150V is applied to the piezoelectric drive means and a 1 bar back pressure is applied to the pump membrane. Bend). As can be seen from FIG. 7D, although the temperature expansion coefficient of the silicon pump membrane is smaller than the temperature expansion coefficient of the piezoelectric material of the piezoelectric driving means, it is compared with the manufacturing voltage of 73.6 V in FIGS. 7B and 7C. The higher production voltage of 178V has the effect of pre-blowing the thick silicon pump membrane in advance, ie the pre-given bulge to the pump membrane with different temperature coefficients is overcompensated by applying the production voltage Is done. For these manufacturing parameters, a pre-bulge height of approximately 7.5 μm can be achieved in the central part of the pump membrane. When a negative drive voltage is applied (see reference numeral 732), the pump membrane deflects upward, but when a positive drive voltage is applied, the pump membrane deflects downward toward the pump body (see Reference 736).

  As can be seen, the pump membrane abuts the pump chamber floor or the pump body, even though a 1 bar back pressure is applied. The counter pressure P causes a slight deflection of the pump membrane at the edge. When no reverse pressure is applied (P = 0 mbar), the pump membrane fully contacts the pump chamber floor because the pre-given bulge is adapted to deformations caused by the actuation of the piezoelectric drive means. is there. The remaining dead volume under the pump membrane 736 is about 11.5 nL and occurs only in the case of the back pressure described above. However, these dead volumes are small compared to a total stroke volume of about 163 nL (the volume between pump membrane shapes 732 and 736).

  Summarizing the foregoing, an embodiment of a method of manufacturing a pre-expanded pump membrane provides a wide variety of combinations of pump membrane material and drive means, eg, piezoelectric drive means, for example, a micro pump must be achieved. Manufacturing parameters such as manufacturing signals, manufacturing voltages and / or manufacturing temperatures corresponding to predetermined operating parameters, such as stroke height, stroke volume, compression ratio, back pressure, etc., can be flexibly adjusted.

  Since almost any signal value or voltage value can be used as a production value or a production voltage, the drive means is contracted and pre-inflated using a manufacture signal to join the contracted drive means to the pump membrane An example of a method for manufacturing a pump membrane is very flexible. In this way, almost any pre-bulge height, stroke height and stroke volume can be achieved.

  When adhesives are used to adhere the drive means to the pump membrane, the adhesives generally have a manufacturing temperature that is specific to the adhesive in which they must be cured. Their manufacturing temperature is generally higher than the ambient room temperature. Depending on the height of the manufacturing temperature and the difference between the manufacturing temperature and the operating temperature, a micro pump or generally a flexure transducer is later used, and during normal operation of the pump membrane, the pump membrane and drive means pre- Stress and potentially pre-swelling are inherently caused when the drive means and the pump membrane have different temperature expansion coefficients. By selecting the appropriate drive means and pump membrane material, e.g. the respective piezoceramic and steel or synthetic material for the membrane, the prestress effect caused by the different temperature expansion coefficients can be It can be used to increase the pre-given bulge. The same considerations apply to other bonding methods using bonding materials, such as soldering.

  Both effect considerations can use a pump membrane material, such as a silicon pump membrane, which typically causes a pre-given bulge downward but has a smaller coefficient of thermal expansion than the piezoelectric drive means. However, by applying a more appropriate manufacturing signal or manufacturing value, the bulge previously given downward can be compensated more greatly to finally achieve the bulge previously given upward.

  In other words, the specific example in which the second thermal expansion coefficient (the thermal expansion coefficient of the driving means made of the second material) is higher than the first thermal expansion coefficient (the thermal expansion coefficient of the film made of the first material). In the first direction of the pump membrane produced by cooling the driving means and the pump membrane joined with a bulge previously applied in the first direction of the pump membrane produced by releasing the production signal. In this way, the bulge given in advance in the second direction opposite to the direction is compensated more greatly.

  Thus, a further embodiment of the method of producing a pre-expanded pump membrane is based on the first and second values based on a predetermined back pressure value assuming that the pump membrane assumes a second position when the drive means is activated. For example, automatically determining material and / or manufacturing signal values.

  Compared to the pre-swollen method using oxide film on the piezoelectric actuator, the embodiment of the present invention has less material (no oxide film), fewer manufacturing steps (pump film and piezoelectric drive) Without the formation of an oxide film between the means) and is more adaptive with respect to achievable stroke volume and stroke height, providing a higher stroke height and stroke volume.

  In certain embodiments, the pump chamber has a first volume when the pump membrane is in a first bulge position and a second volume when the pump membrane is in a second less bulge position. The second volume is smaller than the first volume, the pump membrane, pump body and passive inlet and outlet check valves have a compression ratio greater than 50 or greater than 100, and the compression ratio is the micro pump stroke volume. The drive means is joined to the pump membrane such that the stroke volume is defined by the difference between the first volume and the second volume. The second volume can be, for example, the volume of the valve well in the pump body at the passive inlet and / or outlet check valve portion, and / or the depression in the passive inlet or outlet check valve itself, and / or Defined essentially by an anti-adhesion means configured to avoid the pump membrane sticking to the first surface of the pump body when the pump membrane is in the second position.

  Another embodiment can use laser bonding or other bonding techniques to bond the drive means to the pump membrane, and is described above to achieve pre-stress and potentially pre-given bulge of the bending actuator. So apply manufacturing signal during bonding.

  In a further embodiment, the drive means causes the pump membrane to be activated first (eg, by applying a negative voltage to the piezoelectric drive means) before it moves the pump membrane toward the second less bulge position. 3 can be configured to move to a more swollen position.

  In the following, an embodiment of a microvalve consisting of a bending transducer manufactured according to an embodiment of the invention will be described.

  7E, 7F, 7FF and FIG. 7G show cross-sectional schematic views of a normally closed micro valve 700. FIG. FIGS. 7E and 7F show the microvalve in a non-actuated self-blocking state where no operating or drive voltage is applied (U = 0V) and the valve is closed. FIG. 7E shows a side view with an inlet port, while FIG. 7F shows a side view rotated 90 ° with an outlet port. 7FF and 7G show the open micro valve. A positive operating voltage or drive voltage is applied (U> 0V). FIG. 7FF shows the same side view as FIG. 7E, i.e. a side view with an inlet port (but open), and FIG. 7G shows the same side view as FIG. 7F, i.e. a side view with an outlet port (but open). And shows the same side view. The microvalve has a similar design to the microvalves described in US patent application publication US 2004 / 0036047A1 and US patent application publication US 2006 / 0027772A1. As can be seen in FIGS. 7E-7G, the microvalve 700 includes a first or operating chip 740 and a second or flap chip 750. The operating chip 740 has a recess or indentation 742 on the first major side or surface 744 (upper surface with respect to FIGS. And a film 110 formed between 743 and 743. Driving means, such as piezoelectric ceramic, is disposed on the first surface or side surface 112 of the membrane 110. The tappet 746 protrudes on the second opposing surface 114 of the membrane 110. The first tip 740 further includes a sealing lip 748 that projects from the second surface 114 of the membrane 110, such as a tappet 746. The second tip 750 includes a fluid inlet 752 (see FIGS. 7E and 7FF) and a fluid or valve outlet 754 (see FIGS. 7F and 7G) formed in the second tip. Further, the second tip 750 includes a flexible shutter or closure element 754 that is mechanically connected to the membrane 110 via a tappet 746. As can be seen from FIGS. 7F and 7G, the shutter includes a recess 756 disposed on the opposite surface of the membrane so that it can be deflected or moved downward when the drive means 210 is operated. As can be seen from FIG. 7E, the seal lip 748 fluidly separates or seals the valve inlet 752 from a recess 743, also referred to as a valve chamber recess 743, when the drive means is not activated. When the drive means 210 operates, the bending transducer and membrane 110 formed by the drive means 210 bend down and simultaneously bend the shutter 754 downward to form a fluid connection between the valve inlet 752 and the valve chamber recess 743. To open the valve (see FIG. 7FF). As can be seen from FIGS. 7F and 7G, the outlet port 754 is always in fluid connection with the valve chamber recess 740. In other words, by operating the drive means 210, the valve inlet 752 is fluidly connected to the valve outlet 754 via the valve chamber recess 743.

  The first chip 740 and the second chip 750 can be formed of silicon or any other material. However, if the first and second chips 740, 750 are silicon or other semiconductor chips, the adhesion of the drive means 210 with an adhesive that requires a specific manufacturing temperature for curing is not possible with the shutter. Unnecessary swelling previously given to the pump membrane 110 toward 754 may be reached, reducing the sealing reliability of the normally closed valve 700. Similar considerations apply to other bonding methods that perform or require heating of the two chips.

  Embodiments of the present invention can compensate for or overcompensate a pre-given bulge in the direction of the shutter 754 by applying a manufacturing signal, eg, a positive manufacturing voltage in the case of the piezoelectric actuator 210. The pre-stress of the driving means according to the embodiment of the present invention, for example, the piezoelectric driving means, has the effect that the micro valve is closed safely or securely. Already a small prestress of the drive means is sufficient to ensure a normally closed valve. Furthermore, the threshold pressure at which the valve remains closed when a backward pressure is applied can be easily adjusted by applying an appropriate manufacturing signal.

  FIG. 7H shows an example of a normally open microvalve that includes a first chip 740 and a second chip 750. The first chip 740 includes a recess 742 on the first side surface 744 so as to form the valve film 110. On the first side 112 of the film 110 on the opposite side of the second chip 750, a driving means, for example a piezoelectric driving means 210 is bonded to the film 110. The driving means 210 and the membrane 110 form a bending transducer. The first chip 740 is connected to the second chip 750 via a second surface or side 745 opposite the first surface or side 744. The second chip 750 includes a valve input 752 formed by a through hole extending from the side facing the first chip of the second chip to the opposite side of the second chip, and a second input similar to the valve input 752. And a valve output 754 formed by a through hole extending from the first side of the chip facing the first chip toward the opposite second side or surface. A recess 758 is formed in the first side of the second tip 750 to define a valve seat or valve lip 759.

  The driving means 210 is bonded to the film 110 according to an embodiment of the present invention and pre-inflated in a direction facing away from the second chip. Thus, when the drive means 210 is not activated, the valve inlet 752 and valve outlet 754 are in fluid connection and the valve is opened. When the drive means 210 is activated, the drive means 210 moves the membrane 110 down until it contacts the valve lip 759 to seal or close the valve.

  FIG. 7I shows a further embodiment of a normally open valve similar to the normally open micro valve of FIG. 7H. In contrast to the microvalve of FIG. 7H, the microvalve of FIG. 7I protrudes from a further recess 743 formed in the second side 745 of the first chip and the second side of the valve membrane 110. A tappet 746. Tappet 746 is disposed opposite valve inlet 752 and valve seal 759.

  The driving means 210 is bonded to the film 110 according to an embodiment of the present invention and is inflated in advance. When the drive means 210 is not activated, the valve inlet 752 is in fluid connection with the valve outlet 754 due to the pre-inflated shape of the membrane 110. When the drive means 210 is activated, the membrane moves to the second tip and the tappet 746 contacts the valve lip 759 and closes the valve.

  The embodiment of the microvalve shown in FIGS. 7H and 7I with a pre-inflated membrane is advantageous with respect to production technology as well as functional advantages. If the membrane is formed of silicon or other semiconductor material, the spacing element or structure between the valve seat or lip and the closure element (membrane or tappet) should not be foreseen. Thus, a reduction in one mask, one lithography and one etching step is required, thus reducing manufacturing costs and complexity.

  When the normally open valve is closed, the membrane or tappet is in a flat state. In particular, in the case of non-circular valve seats or lips, or even serpentine shaped valve seats (used to increase flow), avoid the remaining gaps that are provided when the membrane is biased to close the valve Can be done. Thus, embodiments of the present invention provide microvalves with excellent sealing properties that are easy to design and manufacture.

  Previous progress was described with the figures, especially with respect to that particular embodiment. It is well understood by those skilled in the art that various other modifications in shape and detail can be made without departing from the spirit and scope thereof. Accordingly, it is understood that various modifications can be made in adapting different embodiments without departing from the superordinate concepts disclosed herein and can be understood by the following claims. The

Claims (20)

A method of manufacturing a bending transducer comprising a driving means and a membrane, the method comprising:
Preparing the membrane (110) and the drive means (210) (1010), and during the joining of the drive means to the membrane (110) so that the drive means is prestressed after joining Applying (1020) a manufacturing signal ( _U20 ) to (210), wherein the manufacturing signal is of the same type as the operating signal that operates the flexure transducer. The method according to claim 1, wherein the production signal (U _production ) is only opened after the joining is finished.   The method according to claim 1 or 2, wherein the bonding is performed by a bonding material disposed between the drive means and the membrane, and the manufacturing signal is only released after the bonding material is cured.   4. A method according to claim 2 or claim 3, wherein the bonding material is an adhesive or a soldering material.   5. Any one of claims 2 to 4, wherein during the joining of the driving means to the membrane, the driving means is pressed against the membrane (110) and the pressing is only terminated after the bonding material has hardened. The method of crab.   The method according to any of the preceding claims, wherein the manufacturing signal is such that the drive means (210) is in a contracted state during bonding.   The manufacturing signal has a pre-bulged shape that, after bonding, has a bulge that the bending transducer (110, 210) is pre-applied in the direction of the driving means in relation to the bonding surface between the driving means and the membrane. The method according to any one of claims 1 to 6, wherein: The method according to any of claims 1 to 7, wherein the driving means (210) is a piezoelectric driving means and the manufacturing signal (U _production ) is a manufacturing voltage.   The temperature coefficient of the film (110) is larger than the temperature coefficient of the driving means (210), and the bonding of the driving means (210) to the film (110) is at a manufacturing temperature higher than the operating temperature at which the driving means operates later. 9. A method according to any of the preceding claims, wherein the method is performed and the manufacturing signal is such that the drive means (210) is in a contracted state during bonding. 10. The drive means (210) is a piezoelectric drive means (210), the production signal is a positive production voltage (U _production ), and the membrane (110) comprises a metal or a synthetic material. the method of.   The temperature coefficient of the film (110) is smaller than the temperature coefficient of the driving means (210), and the bonding of the driving means (210) to the film (110) is higher than the operating temperature at which the driving means operates later. And the manufacturing signal is a second type of prestress where the first type of prestress caused by applying the manufacturing signal is caused by a different temperature coefficient in the opposite direction to the first type of prestress. 9. A method according to any of claims 1 to 8, which is such as to compensate more greatly. The method of claim 11, wherein the driving means is a piezoelectric driving means, the manufacturing signal is a positive manufacturing voltage (U _production ), and the film comprises a semiconductor material. A method of manufacturing a micropump, wherein the micropump includes a bending transducer having a membrane (110) and a drive means (210), the membrane forming a pump membrane, and the first being driven by the drive means. A pump body configured to move between a bulge position and a second less bulge position, and further connected to the pump membrane to define a pump chamber between the pump body and the pump membrane ( 120), the method comprising:
A bending transducer (110, 210) is produced by the method of any of claims 1 to 12, such that the pump membrane assumes a pre-bulged shape at a first bulged position when the drive means is not activated. A method comprising the steps of: A method of manufacturing a micro-valve, wherein the micro-valve includes a bending transducer having a membrane and a drive means, the membrane forming a valve membrane and being actuated by the drive means to open and close the micro-valve. Configured to move between a first position and a second position, the method comprising:
A method comprising the step of manufacturing a bending transducer by the method according to any of claims 1-12.   The first position is a swollen position, the second position is a position that is less swollen, and the valve membrane is manufactured so as to take a pre-swollen shape at the first swollen position when the driving means does not operate. The method of claim 14, wherein:   After the manufacture of the bending transducer, the driving means (210) is arranged in the micro-valve so that the driving means cannot be bent in the direction of the driving means with respect to the joint surface between the driving means and the membrane. 15. The method of claim 14, wherein bonding of the drive means is performed such that the drive means is prestressed to bend in that direction. A micro pump,
A flexure transducer comprising a membrane (110) and drive means (210), said membrane forming a pump membrane (110) of a micropump, wherein said drive means (210) has a first inflated position and a second Configured to move between positions with less bulge,
A pump body (120) joined to the pump membrane (110) to define a pump chamber between the pump body and the pump membrane;
13. The bending transducer is manufactured by the method of any of claims 1 to 12, wherein when the drive means is inoperative, the pump membrane (110) assumes a pre-bulge shape at a first bulge position. , Micro pump.   18. The micro pump of claim 17, wherein the micro pump includes an inlet check valve and an outlet check valve that are both fluidly connected to the pump chamber and disposed in the pump body so as to face the pump membrane.   The pump body (120) includes a first surface disposed opposite a pump membrane (110) that is essentially flat, the pump membrane having a basically planar shape in a second position; The micro pump according to claim 17 or claim 18. A micro valve,
A flexure transducer comprising a membrane (110) and a drive means (210), said membrane (110) forming a valve membrane of a valve and a first position by said drive means to open and close the micro-valve 13. A micro valve configured to move between a second position and the flexure transducer manufactured by the method of any of claims 1-12.

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